If you read the entirely of this thread you'd wonder how reliable 964s are. Well, I can say that the amount of work done doesn't reflect breakage, just my OCD nature.

Buying a new set of pistons and cylinders falls into that category. I have no doubt the originals would have been ok, but I want perfect and I'm very happy with what arrived from Autobahn.

Everything looks in great condition and there are only 2 grams weight difference across all 6 pistons. That said, these are 11 grams heavier than my existing pistons so I have decided to fit them as a set rather than mix and match with my existing set. More cleaning required.

Cleaning the pistons and cylinders allowed me to see the numbers on each. The new pistons were produced five months later than my originals. They also appear to have the cylinder number stamped on all but one.

Unfortunately these numbers don't correspond to the cylinder numbers the pistons were packed in. While everything is the same tolerance group I don't want to make an assumption that bites me in the backside later so I'm taking them to a machine shop for measurement. That way I can be sure that the cylinders and pistons are matched for consistent tolerances.

By the way, the pistons ex carbon deposits and rings are within 1 gram of each other (5 of them are the same weight). Fritz was on his game when this set was matched.

Another of the engine out jobs on the list was a power steering pump rebuild. Mine wasn't leaking but I didn't want to do this with the engine in, which it would eventually require and the Rennbay kit was reasonably priced.

There are DIY instructions in the forum and Rennbay have a YouTube video. It's relatively easy except for the circlip, which I had to slightly bend to remove. It is easy to rebend when installing. Now I need to replace the lower seal and O ring which may not be in my gasket sets.

I've got this on my to do list when I pull the motor. Can you expand on the detail of the hourglass shaped seal and the reinforcement that goes inside? Does that metal or plastic reinforcement just lay in from the top?

I've got this on my to do list when I pull the motor. Can you expand on the detail of the hourglass shaped seal and the reinforcement that goes inside? Does that metal or plastic reinforcement just lay in from the top?

Thanks!

The rubber seal goes in first. It is flat on the bottom but has a bevel on the top side. The hard plastic seal slips in around the outside of the rubber seal. It's a tight fit, but not difficult to fit or keep in place.

Btw instructions say to mark the pump housing before opening it. That is unnecessary as there are cast marks on the case and it's obvious how it goes back together.

The rebuild is stalled waiting on parts so I had a big garage clean up in pre build preparation (yes, that is clean for me)

All of the existing parts have been cleaned and measured so when the parts arrive it will be like an operating theatre as it all goes back together with (sort of) clean room cleanliness and military precision.

Btw it's easy to take your time when you have a spare 964 to drive in the meantime